Procedure for operating a particle sensor that is arranged downstream after a particle filter and device for implementing this procedure

Abstract

A procedure for operating a particle sensor that is arranged downstream after a particle filter, at which an ash contamination can occur, and a device for implementing the procedure, are suggested. A remaining operating time determination determines the remaining operating time of the particle sensor related to an ash contamination. Alternatively or additionally the remaining operating time determination provides a correction signal, with which the sensitivity loss of the particle sensor caused by the ash contamination can be considered.

1. A method of operating a particle sensor arranged downstream after a particle filter wherein an ash contamination of the particle sensor can occur, the method comprising:
 determining a remaining operating time of the particle sensor related to the ash contamination via a remaining operating time determination, whereby a correction signal is provided such that a sensitivity loss of the particle sensor due to the ash contamination is considered. 
 
     
     
       2. A method according to  claim 1 , wherein determining includes determining the remaining operating time of the particle sensor from a first activation of the particle sensor. 
     
     
       3. A method according to  claim 1 , wherein determining includes determining after a detection of a particle filter defect, wherein an assessment of a particle sensor-sensor signal is used to detect the particle filter defect. 
     
     
       4. A method according to  claim 3 , wherein the assessment includes a comparison of the particle sensor-sensor signal with an absolute threshold value and/or a gradient threshold value. 
     
     
       5. A method according to  claim 1 , further comprising determining an efficiency of the particle filter by the remaining operating time determination as a defect intensity. 
     
     
       6. A method according to  claim 5 , wherein determining an efficiency includes:
 a) determining by a particle sensor measuring signal related to an entire operating time of a combustion engine, wherein the particle filter and the particle sensor are arranged in an exhaust gas area of the combustion engine and relating to a driving distance that has been covered by a motor vehicle, wherein the motor vehicle provides a combustion engine as a drive. 
 
     
     
       7. A method according to  claim 5 , wherein determining an efficiency includes determining via a particle sensor measuring signal and an ash emission of the combustion engine that has been calculated by an ash model. 
     
     
       8. A method according to  claim 1 , wherein determining includes considering an ash emission of a combustion engine that has been determined by means of an ash model. 
     
     
       9. A method according to  claim 8 , wherein the ash model considers at least:
 a) a fuel type of the combustion engine; 
 b) a measure of an oil consumption of the combustion engine; 
 c) an oil quality of the combustion engine; 
 d) a load of the combustion engine; 
 e) a temperature of the combustion engine; and 
 f) an entire operating time of the combustion engine. 
 
     
     
       10. A method according to  claim 1 , wherein determining includes considering an entire operating time of the particle sensor or the driving distance that has been covered by a motor vehicle, wherein the drive of the motor vehicle is a combustion engine, wherein a particle filter and the particle sensor are arranged in the exhaust gas area of the combustion engine. 
     
     
       11. A method according to  claim 1 , further comprising at least partially minimizing an operating voltage of the particle sensor in order to minimize an ash accumulation. 
     
     
       12. A method according to  claim 1 , wherein the particle sensor is provided at least temporally with a sensor heating voltage in order to minimize an ash accumulation. 
     
     
       13. A device, comprising:
 a customized controller constructed and configured to operate a particle sensor arranged downstream after a particle filter, wherein an ash contamination of the particle sensor can occur, and to determine a remaining operating time of the particle sensor related to the ash contamination via a remaining operating time determination, whereby a correction signal is provided such that a sensitivity loss of the particle sensor due to the ash contamination is considered. 
 
     
     
       14. A device according to  claim 13 , wherein at least one customized controller is provided additionally to a combustion engine controller as a separate sensor controller, wherein the sensor controller contains at least a remaining operating time determination. 
     
     
       15. A device according to  claim 14 , wherein the at least one controller contains a measuring signal assessment, a defect intensity determination and an ash model. 
     
     
       16. A computer-implemented method for operating a particle sensor arranged downstream after a particle filter, wherein an ash contamination of the particle sensor can occur, the computer-implemented method comprising the step of: determining a remaining operating time of the particle sensor related to the ash contamination via a remaining operating time determination, whereby a correction signal is provided such that a sensitivity loss of the particle sensor due to the ash contamination is considered. 
     
     
       17. A computer program product with a program code stored on a machine readable device and executed on a customized controller, for operating a particle sensor arranged downstream after a particle filter, wherein an ash contamination of the particle sensor can occur, the program code including instructions for determining a remaining operating time of the particle sensor related to the ash contamination via a remaining operating time determination, whereby a correction signal is provided such that a sensitivity loss of the particle sensor due to the ash contamination is considered.